mssqlspatial.cs

C# 的地图开发例子（sharp map)

// Copyright 2006 - Ricardo Stuven ([e-mail])
// Copyright 2006 - Morten Nielsen (www.iter.dk)
//
// MsSqlSpatial provider by Ricardo Stuven.
// Based on PostGIS provider by Morten Nielsen.
//
// This file is part of SharpMap.
// SharpMap is free software; you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
// 
// SharpMap is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Lesser General Public License for more details.

// You should have received a copy of the GNU Lesser General Public License
// along with SharpMap; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA 

using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Text;
using System.Data.SqlClient;

namespace SharpMap.Data.Providers
{
	/// <summary>
	/// Microsoft SQL Server 2005 / MsSqlSpatial dataprovider
	/// </summary>
	/// <example>
	/// Adding a datasource to a layer:
	/// <code lang="C#">
	/// SharpMap.Layers.VectorLayer myLayer = new SharpMap.Layers.VectorLayer("My layer");
	/// string ConnStr = @"Data Source=localhost\sqlexpress;Initial Catalog=myGisDb;Integrated Security=SSPI;";
	/// myLayer.DataSource = new SharpMap.Data.Providers.MsSqlSpatial(ConnStr, "myTable", "myId");
	/// </code>
	/// </example>
	[Serializable]
	public class MsSqlSpatial : SharpMap.Data.Providers.IProvider, IDisposable
	{
		/// <summary>
		/// Initializes a new connection to MsSqlSpatial
		/// </summary>
		/// <param name="ConnectionStr">Connectionstring</param>
		/// <param name="tablename">Name of data table</param>
		/// <param name="geometryColumnName">Name of geometry column</param>
		/// /// <param name="OID_ColumnName">Name of column with unique identifier</param>
		public MsSqlSpatial(string ConnectionStr, string tablename, string geometryColumnName, string OID_ColumnName)
		{
			this.ConnectionString = ConnectionStr;
			this.Table = tablename;
			this.GeometryColumn = geometryColumnName;
			this.ObjectIdColumn = OID_ColumnName;
		}

		/// <summary>
		/// Initializes a new connection to MsSqlSpatial
		/// </summary>
		/// <param name="ConnectionStr">Connectionstring</param>
		/// <param name="tablename">Name of data table</param>
		/// <param name="OID_ColumnName">Name of column with unique identifier</param>
		public MsSqlSpatial(string ConnectionStr, string tablename, string OID_ColumnName) : this(ConnectionStr,tablename,"",OID_ColumnName)
		{
			this.GeometryColumn = this.GetGeometryColumn();
		}

		private bool _IsOpen;

		/// <summary>
		/// Returns true if the datasource is currently open
		/// </summary>
		public bool IsOpen
		{
			get { return _IsOpen; }
		}

		/// <summary>
		/// Opens the datasource
		/// </summary>
		public void Open()
		{
			//Don't really do anything. SqlClient's ConnectionPooling takes over here
			_IsOpen = true;
		}
		/// <summary>
		/// Closes the datasource
		/// </summary>
		public void Close()
		{
			//Don't really do anything. SqlClient's ConnectionPooling takes over here
			_IsOpen = false;
		}
	

		#region Disposers and finalizers
		private bool disposed = false;

		/// <summary>
		/// Disposes the object
		/// </summary>
		public void Dispose()
		{
			Dispose(true);
			GC.SuppressFinalize(this);
		}

		internal void Dispose(bool disposing)
		{
			if (!disposed)
			{
				if (disposing)
				{
					//Close();
				}
				disposed = true;
			}
		}

		/// <summary>
		/// Finalizer
		/// </summary>
		~MsSqlSpatial()
		{
			Dispose();
		}
		#endregion

		private string _ConnectionString;

		/// <summary>
		/// Connectionstring
		/// </summary>
		public string ConnectionString
		{
			get { return _ConnectionString; }
			set { _ConnectionString = value; }
		}

		private string _Table;

		/// <summary>
		/// Data table name
		/// </summary>
		public string Table
		{
			get { return _Table; }
			set { _Table = value; }
		}

		private string _GeometryColumn;

		/// <summary>
		/// Name of geometry column
		/// </summary>
		public string GeometryColumn
		{
			get { return _GeometryColumn; }
			set { _GeometryColumn = value; }
		}

		private string _GeometryExpression = "{0}";
		/// <summary>
		/// Expression template for geometry column evaluation.
		/// </summary>
		/// <example>
		/// You could, for instance, simplify your geometries before they're displayed.
		/// Simplification helps to speed the rendering of big geometries.
		/// Here's a sample code to simplify geometries using 100 meters of threshold.
		/// <code>
		/// datasource.GeometryExpression = "ST.Simplify({0}, 100)";
		/// </code>
		/// Also you could draw a 20 meters buffer around those little points:
		/// <code>
		/// datasource.GeometryExpression = "ST.Buffer({0}, 20)";
		/// </code>
		/// </example>
		public string GeometryExpression
		{
			get { return _GeometryExpression; }
			set { _GeometryExpression = value; }
		}

		private string _ObjectIdColumn;

		/// <summary>
		/// Name of column that contains the Object ID
		/// </summary>
		public string ObjectIdColumn
		{
			get { return _ObjectIdColumn; }
			set { _ObjectIdColumn = value; }
		}
	

		/// <summary>
		/// Returns geometries within the specified bounding box
		/// </summary>
		/// <param name="bbox"></param>
		/// <returns></returns>
		public Collection<Geometries.Geometry> GetGeometriesInView(SharpMap.Geometries.BoundingBox bbox)
		{
			Collection<Geometries.Geometry> features = new Collection<SharpMap.Geometries.Geometry>();
			using (SqlConnection conn = new SqlConnection(_ConnectionString))
			{
				string strSQL = "SELECT ST.AsBinary(" + this.BuildGeometryExpression() + ") ";
				strSQL += "FROM ST.FilterQuery" + this.BuildSpatialQuerySuffix() + "(" + this.BuildEnvelope(bbox) + ")";

				if (!String.IsNullOrEmpty(_definitionQuery))
					strSQL += " WHERE " + this.DefinitionQuery;

				using (SqlCommand command = new SqlCommand(strSQL, conn))
				{
					conn.Open();
					using (SqlDataReader dr = command.ExecuteReader())
					{						
						while (dr.Read())
						{
							if (dr[0] != DBNull.Value)
							{
								SharpMap.Geometries.Geometry geom = SharpMap.Converters.WellKnownBinary.GeometryFromWKB.Parse((byte[])dr[0]);
								if(geom!=null)
									features.Add(geom);
							}
						}				
					}
					conn.Close();
				}
			}
			return features;
		}

		/// <summary>
		/// Returns the geometry corresponding to the Object ID
		/// </summary>
		/// <param name="oid">Object ID</param>
		/// <returns>geometry</returns>
		public SharpMap.Geometries.Geometry GetGeometryByID(uint oid)
		{
			SharpMap.Geometries.Geometry geom = null;
			using (SqlConnection conn = new SqlConnection(_ConnectionString))
			{
				string strSQL = "SELECT ST.AsBinary(" + this.BuildGeometryExpression() + ") AS Geom FROM " + this.Table + " WHERE " + this.ObjectIdColumn + "='" + oid.ToString() + "'";
				conn.Open();
				using (SqlCommand command = new SqlCommand(strSQL, conn))
				{
					using (SqlDataReader dr = command.ExecuteReader())
					{
						while (dr.Read())
						{
							if (dr[0] != DBNull.Value)
								geom = SharpMap.Converters.WellKnownBinary.GeometryFromWKB.Parse((byte[])dr[0]);
						}
					}
				}
				conn.Close();
			}
			return geom;
		}
		/// <summary>
		/// Returns geometry Object IDs whose bounding box intersects 'bbox'
		/// </summary>
		/// <param name="bbox"></param>
		/// <returns></returns>
		public Collection<uint> GetObjectIDsInView(SharpMap.Geometries.BoundingBox bbox)
		{
			Collection<uint> objectlist = new Collection<uint>();
			using (SqlConnection conn = new SqlConnection(_ConnectionString))
			{
				string strSQL = "SELECT * FROM ST.FilterQuery('" + this.Table + "', '" + this.GeometryColumn + "', " + this.BuildEnvelope(bbox) + ")";

				if (!String.IsNullOrEmpty(_definitionQuery))
					strSQL += " WHERE " + this.DefinitionQuery;

				using (SqlCommand command = new SqlCommand(strSQL, conn))
				{
					conn.Open();
					using (SqlDataReader dr = command.ExecuteReader())
					{
						while (dr.Read())
						{
							if (dr[0] != DBNull.Value)
							{
								uint ID = (uint)(int)dr[0];
								objectlist.Add(ID);
							}
						}
					}
					conn.Close();
				}
			}
			return objectlist;
		}

		/// <summary>
		/// Returns all objects within a distance of a geometry
		/// </summary>
		/// <param name="geom"></param>
		/// <param name="distance"></param>
		/// <returns></returns>
		[Obsolete("Use ExecuteIntersectionQuery instead")]
		public SharpMap.Data.FeatureDataTable QueryFeatures(SharpMap.Geometries.Geometry geom, double distance)
		{
			//List<Geometries.Geometry> features = new List<SharpMap.Geometries.Geometry>();
			using (SqlConnection conn = new SqlConnection(_ConnectionString))
			{
				string strGeom = "ST.GeomFromText('" + geom.AsText() + "', " + this.SRID.ToString() + ")";

				string strSQL = "SELECT *, ST.AsBinary(" + this.BuildGeometryExpression() + ") As sharpmap_tempgeometry ";
				strSQL += "FROM ST.IsWithinDistanceQuery" + this.BuildSpatialQuerySuffix() + "(" + strGeom + ", " + distance.ToString(Map.numberFormat_EnUS) + ")";

				if (!String.IsNullOrEmpty(_definitionQuery))
					strSQL += " WHERE " + this.DefinitionQuery;

				using (SqlDataAdapter adapter = new SqlDataAdapter(strSQL, conn))
				{
					System.Data.DataSet ds = new System.Data.DataSet();
					conn.Open();
					adapter.Fill(ds);
					conn.Close();
					if (ds.Tables.Count > 0)
					{
						FeatureDataTable fdt = new FeatureDataTable(ds.Tables[0]);
						foreach (System.Data.DataColumn col in ds.Tables[0].Columns)
							if (col.ColumnName != this.GeometryColumn && !col.ColumnName.StartsWith(this.GeometryColumn + "_Envelope_") && col.ColumnName != "sharpmap_tempgeometry")
								fdt.Columns.Add(col.ColumnName,col.DataType,col.Expression);
						foreach (System.Data.DataRow dr in ds.Tables[0].Rows)
						{
							SharpMap.Data.FeatureDataRow fdr = fdt.NewRow();
							foreach(System.Data.DataColumn col in ds.Tables[0].Columns)
								if (col.ColumnName != this.GeometryColumn && !col.ColumnName.StartsWith(this.GeometryColumn + "_Envelope_") && col.ColumnName != "sharpmap_tempgeometry")
									fdr[col.ColumnName] = dr[col];
							if (dr["sharpmap_tempgeometry"] != DBNull.Value)
								fdr.Geometry = SharpMap.Converters.WellKnownBinary.GeometryFromWKB.Parse((byte[])dr["sharpmap_tempgeometry"]);
							fdt.AddRow(fdr);								
						}
						return fdt;
					}
					else return null;
				}
			}
		}

		/// <summary>
		/// Returns the features that intersects with 'geom'
		/// </summary>
		/// <param name="geom"></param>
		/// <param name="ds">FeatureDataSet to fill data into</param>
		public void ExecuteIntersectionQuery(SharpMap.Geometries.Geometry geom, FeatureDataSet ds)
		{
			List<Geometries.Geometry> features = new List<SharpMap.Geometries.Geometry>();
			using (SqlConnection conn = new SqlConnection(_ConnectionString))
			{
				string strGeom = "ST.GeomFromText('" + geom.AsText() + "', " + this.SRID.ToString() + ")";

				string strSQL = "SELECT *, ST.AsBinary(" + this.BuildGeometryExpression() + ") As sharpmap_tempgeometry ";
				strSQL += "FROM ST.RelateQuery" + this.BuildSpatialQuerySuffix() + "(" + strGeom + ", 'intersects')";

				if (!String.IsNullOrEmpty(_definitionQuery))
					strSQL += " WHERE " + this.DefinitionQuery;

				using (SqlDataAdapter adapter = new SqlDataAdapter(strSQL, conn))
				{
					conn.Open();